Study on the social security culture of the Song dynasty 并列题名：Study on the social security culture of the Song dynasty Study of local security management of the Han dynasty Study on the literature of Chen dynasty Study on the social security of peasant-workers Study on the poetry circle of Huizhou in the Song dynasty Research on the social structure of pre-Qin Dynasty Study on financial system transition of the ming dynasty Study of urban security in the Han dynasty 并列题名：Study of local security management of the Han dynasty